Semiconductor package with passive device integration

ABSTRACT

A system is provided for an integrated circuit package including a leadframe with a lead finger. A groove is in a lead finger for a conductive bonding agent and a passive device is in the groove to be held by the conductive bonding agent.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This is a Divisional of co-pending application Ser. No. 10/773,716 filedFeb. 5, 2004, which is hereby incorporated by reference herein.

TECHNICAL FIELD

The present invention relates generally to semiconductor integratedcircuit packages, and more specifically to packages with leadframes forpassive devices.

BACKGROUND ART

Digital products, such as cell phones and wrist watches have becomeaspects of everyday life. The core of these digital electronic productsare integrated circuit die which continue to be made smaller and morereliable while increasing performance and speed.

An integrated circuit is typically packaged in a tiny box-type structureusually on the order of a few millimeters per side. The integratedcircuit package generally has cylindrical terminals formed through apassivation layer of the integrated circuit die to square or rectangularcontacts near its edges for directly bonding the integrated circuit dieto a foil-type leadframe that is usually less than 0.5 mm in thickness.The integrated circuit packages are generally wire bonded or ball bondedto the foil-type leadframe. A body of a hardened, insulative encapsulantmaterial then covers the integrated circuit die and the leadframe.

A series of problems related to the integrated circuit package and theleadframe becomes worse as the size of both decrease. Negativeelectrical effects such as electromagnetic interference, or undesirablecoupling between leads in the leadframe, result in slowdown ofelectrical signals, cross-talk, or other problems.

To overcome these problems, passive components have been placed on theleadframe between the leads to eliminate negative electrical effects.These passive devices include capacitors, resistors, and inductors.

With the pressing demand on integrated circuit die to have higherdensity, higher integrity, compact size, and multiple functions, passivedevices have also become smaller and lighter. As a result, they can beintegrated into an integrated circuit package using surface mounttechnology (SMT). However, this has created its own set of problems withmany different types of defects.

Keeping in mind that a passive device may be the size of a grain ofsand, problems such as misalignment, bridging, drawbridging/tombstoning,or missing passive devices may occur. In bridging, the solder used toattach the passive devices may bridge or short-circuit adjacent passivedevices. Misalignment means that the passive devices may only touch thesolder connections so as to provide high resistance, or may actually notcontact the solder connections required so as to produce an opencircuit. Drawbridging/tombstoning occurs when the surface tension ofsolder lifts the passive device off the leadframe and results in an opencircuit. A missing passive device can occur because the devices areextremely small and may be easily dislodged.

Prior developments have not taught or suggested any solutions, and,thus, solutions to these problems have long eluded those skilled in theart.

SUMMARY OF THE INVENTION

The present invention provides a system for an integrated circuitpackage including a leadframe having a lead finger. A groove is in alead finger for a conductive bonding agent and a passive device is inthe groove to be held by the conductive bonding agent.

Certain embodiments of the invention have other advantages in additionto or in place of those mentioned above. The advantages will becomeapparent to those skilled in the art from a reading of the followingdetailed description when taken with reference to the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view of a passive device with a body and conductor metalends;

FIG. 2A is a plan view of an integrated circuit package in accordancewith the present invention;

FIG. 2B is a cross-sectional view of the structure of FIG. 2A takenalong line 2B-2B;

FIG. 3A is a cross-sectional view of an integrated circuit packagesimilar to FIG. 2B of an alternative embodiment of the presentinvention;

FIG. 3B is a cross-sectional view of an integrated circuit packagesimilar to FIG. 3B of a further alternative embodiment of the presentinvention;

FIG. 3C is a cross-sectional view of an integrated circuit packagesimilar to FIG. 3B of a still further alternative embodiment of thepresent invention;

FIG. 4A is a plan view of an integrated circuit package in accordance afurther embodiment of the present invention;

FIG. 4B is a cross-sectional view of the structure of FIG. 4A takenalong line 4B-4B;

FIG. 5A is a plan view of an integrated circuit package according to astill further embodiment of the present invention;

FIG. 5B is a cross-sectional view of the structure of FIG. 5A takenalong line 5B-5B;

FIG. 6A is a plan view of an integrated circuit package according toanother embodiment of the present invention;

FIG. 6B is a cross-sectional view of the structure of FIG. 6A takenalong line 6B-6B;

FIG. 7A is an intermediate step in manufacturing a wire-bondedintegrated circuit package in accordance with the present invention;

FIG. 7B is the structure of FIG. 7A after removing a stencil,positioning the passive devices, and reflow soldering;

FIG. 7C is the structure of FIG. 7B after deposition of a bondingcompound;

FIG. 7D is the structure of FIG. 7C after positioning a wire-bondedintegrated circuit die;

FIG. 7E is the structure of FIG. 7D after bonding wires between awire-bonded integrated circuit die and lead fingers;

FIG. 7F is the structure of FIG. 7E after deposition of an encapsulant;

FIG. 7G is the structure of FIG. 7F after de-tape or removal of theadhesive tape;

FIG. 7H is the structure of FIG. 7G after singulation;

FIG. 7I is the structure of FIG. 7F in an alternate embodiment showingthe formation of solder balls;

FIG. 7J is the structure of FIG. 7I after attaching solder balls andreflowing to form a ball grid array;

FIG. 7K is the structure of FIG. 7J after singulation to form anindividual integrated circuit package for a wire-bonded ball grid arraypackage;

FIG. 8A is an intermediate step in manufacturing a ball-bondedintegrated circuit package in accordance with another alternativeembodiment of the present invention;

FIG. 8B is the structure of FIG. 8A after removal of a stencil andleaving solder paste;

FIG. 8C is the structure of FIG. 8B after attachment of a ball-bondedintegrated circuit;

FIG. 8D is the structure of FIG. 8C after encapsulation;

FIG. 8E is the structure of FIG. 8D after formation of apertures in theadhesive tape;

FIG. 8F is the structure of FIG. 8E inverted for ball attach and reflowof solder balls in the apertures;

FIG. 8G is the structure of FIG. 8F inverted and singulated to form aball-bonded BGA package;

FIG. 8H is the structure of FIG. 8E in an alternate method ofmanufacture in accordance with the present invention;

FIG. 8I is the structure of FIG. 8H after singulation to form theball-bonded integrated circuit package for a solder attach;

FIG. 9A is an intermediate step in manufacturing a ball-bondedintegrated circuit package in accordance with still another alternativeembodiment of the present invention;

FIG. 9B is the structure of FIG. 9A after removal of a stencil leavingsolder paste;

FIG. 9C is the structure of FIG. 9B after a ball-bonded integratedcircuit die is attached, ball bonds formed, and passive devices reflowedinto position;

FIG. 9D is the structure of FIG. 9C after encapsulation in anencapsulant;

FIG. 9E is the structure of FIG. 9D after de-tape or removal of theadhesive tape;

FIG. 9F is the structure of FIG. 9E in an alternate embodiment showingformation of solder balls;

FIG. 9G is the structure of FIG. 9F inverted for ball attach and reflowof the solder balls in the apertures;

FIG. 9H is the structure of FIG. 9F inverted and singulated to form aball-bonded ball grid array package;

FIG. 9I is the structure of FIG. 9F in an alternate method ofmanufacture in accordance with the present invention;

FIG. 9J is the structure of FIG. 9I after singulation to form theball-bonded integrated circuit package for a solder attach;

FIG. 10A is a method for manufacturing a ball-bonded integrated circuitpackage in accordance with another alternative embodiment of the presentinvention;

FIG. 10B is the structure of FIG. 10A after the removal of the stencilleaving the solder paste;

FIG. 10C is the structure of FIG. 10B after a ball-bonded integratedcircuit die is attached, ball bonds formed, and passive devices reflowedinto position;

FIG. 10D is the structure of FIG. 10C after encapsulation;

FIG. 10E is the structure of FIG. 10D after de-tape or removal of theadhesive tape;

FIG. 10F is the structure of FIG. 10D in an alternate embodiment showingthe formation of solder balls;

FIG. 10G is the structure of FIG. 10F in an alternate method ofmanufacture in accordance with the present invention;

FIG. 10H the structure of FIG. 10G after attachment of passive devicesand reflow soldering;

FIG. 10I is the structure of FIG. 10H showing trim and dam-bar cut;

FIG. 10J is the structure of FIG. 10I after forming lead fingers intoexternal leads;

FIG. 11A is a close-up view of a leadframe with a groove in accordancewith the present invention;

FIG. 11B is the structure of FIG. 11A having a passive device in thesolder;

FIG. 12A is one embodiment of a cross-section of FIG. 11B taken alongline 12A-12A;

FIG. 12B is another embodiment of the cross-section of FIG. 11B takenalong line 12B-12B;

FIG. 12C is a further embodiment of the cross-section of FIG. 11B takenalong line 12C-12C; and

FIG. 13 is a close-up plan view of the passive device of FIG. 11B aftersolder reflow; and

FIG. 14 is a flow chart of a method for forming an integrated circuitpackage in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIG. 1, therein is shown a passive device 100 having abody 102 and conductor metal ends 104 and 106.

In the following description, numerous specific details are given toprovide a thorough understanding of the invention. However, it willapparent that the invention may be practiced without these specificdetails. In order to avoid obscuring the present invention, somewell-known system configurations and process steps are not disclosed indetail.

The term “horizontal” as used herein is defined as a plane parallel tothe conventional plane or surface of the integrated circuit package,regardless of its orientation. The term “vertical” refers to a directionperpendicular to the horizontal as just defined. Terms, such as “on”,“above”, “below”, “bottom”, “top”, “over”, and “under”, are defined withrespect to the horizontal plane.

Likewise, the drawings showing embodiments of the invention aresemi-diagrammatic and not to scale and, particularly, some of thedimensions are for the clarity of presentation and are shown greatlyexaggerated in the FIGs. In addition, where multiple embodiments aredisclosed and described having some features in common, for clarity andease of illustration and description thereof like features, one toanother, will ordinarily be described with like reference numerals. Forexample, where structures perform the same function, they will bedescribed with like reference numerals although their shapes andconfigurations may be different.

As will be apparent from the above, using a leadframe with grooves as achip carrier for integration of active die and passive devices,especially for low input/output pin count devices, is an economicallyviable option in comparison to placing the devices on a separatesubstrate. Passive devices can be pre-attached to the grooves withproper opening sizes and locations using surface mount technology (SMT)and/or adhesive dispensing methods. The present invention allowsintegration of passive devices with body sizes longer or shorter thanthe lead pitch or lead width by alterations only in the leadsthemselves.

Further, since the passive devices can be attached into the groovessecurely by a conductive bonding agent, the present invention overcomesor mitigates the disadvantages with surface mounting on the leads or thesubstrate. The groove structure in the leadframe also serves as a meansto reduce the package thickness when incorporating passive devices.

Conventional sheet metal forming methods such as stamping, coining,drilling, etching, etc. can also be readily employed to form therequired groove structures in the leadframes.

For wire-bonded type leadless packages, passive devices may be laid outon the leads surrounding the paddle without interfering with thewire-bonding process.

For ball-bonded leads, passive devices can be set into grooves below theball bonds. No underfill material is required for molded ball-bondedleads on lead packages. The passive device can be connected to any twoleads below the ball bonds rather than the adjacent leads only. For ballbonds, an additional paddle serves as a ground/thermal plane below thedie. Additional solder balls can be attached to further improve theelectrical and thermal performance of the ball bonding. In one of thepreferred embodiments, a stepped paddle profile, or relief, helpsimprove moldability below the ball bonds and prevents void formation.

The number of passive devices on a printed circuit board can also bereduced when the passive devices can be built into the integratedcircuit package. Consequently, the printed circuit board size can bereduced or more room will be provided for external traces routing on theboard.

Wrap-around leaded packages can be formed for higher integration.Package stacking applications can be made or additional passive devicescan be mounted on top of the external leads.

To prevent solder bridging, solder paste reservoirs can be providedalongside the groove. This allows the paste to be printed (or adhesiveto be dispensed) inside the reservoir before or after the passive deviceis temporarily attached to the groove. The gap between the passivedevice and the groove can be filled with solder with capillary effectduring a regular solder reflow operation.

Further, passive devices and high-temperature solder bumps can bereflowed concurrently.

Referring now to FIG. 2A, therein is shown a plan view of an integratedcircuit package 200 in accordance with the present invention. Theintegrated circuit package 200 has a number of lead fingers 201 aroundthe periphery thereof. The lead fingers 201 have generally straight tipsbut may have tips of different configurations, which are used inaccordance with the present invention.

The integrated circuit package 200 further includes a leadframe paddle202, which can be of various configurations, upon which an integratedcircuit die 203 is attached. The integrated circuit die 203 has a numberof contact pads 204 to which a number of wires 205 are attached at oneend and connected to the lead fingers 201 at the other end. The leadfingers 201, the leadframe paddle 202, the integrated circuit die 203,and the wires 205 are embedded in an encapsulant 206. The lead fingers201, the leadframe paddle 202, and the wires 205 are generally made ofconductive materials and the encapsulant 206 is of an insulatingmaterial.

In FIG. 2A, grooves are formed in the lead fingers 201 and/or theleadframe paddle 202.

A medium device configuration 210 is shown with a medium passive device212 extending between lead fingers 214 and 216 having straight tips andlead finger grooves 215 and 217 in the sides, respectively.

The terms “small”, “medium”, and “large” for size are relative to eachdevice configuration or size of device. Generally, a small device and alarge device have widths or lengths between the conductor metal endswhich are respectively smaller or larger than the distance between themain bodies of the structures it must span, such as the distance betweenlead fingers or lead fingers and the leadframe paddle. A medium devicewill have widths or lengths between the conductor metal ends that are inbetween those of small and large devices.

A medium device configuration 220 has a medium passive device 222extending between a lead finger 224, which has an increased tip width,and the leadframe paddle 202. The tip width is increased to accommodatea lead frame groove 225 of medium width for the width of the mediumpassive device 222.

A large device configuration 230 has a large passive device 232 betweena lead finger 234 having an increased tip width and the leadframe paddle202 having a notch 236 for the large width of the large passive device232. The tip width is increased for a lead finger groove 237 and oneside of the notch 236 has a paddle groove 239.

A small device configuration 240 has a small passive device 242extending between a lead finger 244, having a side extension with a leadfinger groove 245 on one side, and a lead finger 246.

A large device configuration 250 has a large passive device 252 betweentwo lead fingers 254 and 256, both of which have flared tips oppositelyoffset so as to accommodate the large passive device 252. The oppositelyoffset tips accommodate the widely separated lead finger grooves 255 and257.

Referring now to FIG. 2B, therein is shown the structure of FIG. 2Ataken along line 2B-2B. The lead finger 216 is shown with the leadfinger groove 217 being a blind groove with a bottom 260. The leadfinger groove 217 is filled with an electrically conductive bondingagent, such as solder 262, and the medium passive device 212 is fittedinto the lead finger groove 217. The medium passive device 212 isattached thereto by the reflow of solder 262.

Referring now to FIG. 3A, therein is shown a cross-section similar toFIG. 2B of another embodiment of the present invention. The leadframepaddle 202 is provided with a blind groove 300 large enough toaccommodate the integrated circuit die 203 and its bonding solder 302.The blind groove 300 helps to prevent epoxy-bleed, reduce the effectiveheight of the integrated circuit die 203 from the bottom of theintegrated circuit package 200, shorten the length of the wires 205, andimprove the adhesion between the leadframe paddle 202 and theencapsulant 206. The depth of the blind groove can be the same as thatof the bottom 260 by being formed by the same process as used to formthe blind grooves, such as the lead finger groove 217.

Also shown in FIG. 3A is a wrap-around lead finger 304 which wrapsaround the outside of the encapsulant 206 so as to connect the mediumpassive device 212 inside the encapsulant 206 with a passive device 308on the outside of the encapsulant 206. This enables additional passivedevice attachment and package stacking of additional integrated circuitdie within the same package.

Referring now to FIG. 3B, therein is shown a structure similar to FIG.3A in another embodiment of the present invention. The leadframe paddle202 is provided with the blind groove 300 into which the integratedcircuit die 203 is placed. A bonding adhesive 310 is deposited and asecond integrated circuit die 312 is stacked over the integrated circuitdie 203. Wires 314 from the second integrated circuit die 312 areconnected to various of the lead fingers 201.

Referring now to FIG. 3C, therein is shown a cross-sectional viewsimilar to FIG. 3B of another embodiment of the present invention. Leadfingers 320 are provided with blind grooves 322 and 324 as well asundercuts 326 which improve adhesion between the lead fingers 320, theleadframe paddle 202, and the encapsulant 206. The blind grooves 322 canbe the same blind grooves used for the lead finger grooves 217 of FIG.3B.

Referring now to FIG. 4A, therein is shown a plan view of an integratedcircuit package 400 in accordance with the present invention with anintegrated circuit die and ball bonds shown by dotted lines. Theintegrated circuit package 400 has a number of lead fingers 401 aroundthe perimeter thereof to which an integrated circuit die 403 is attachedby ball bonds 405. The number of lead fingers 401 is representative ofdifferent types of lead fingers, which may be used in accordance withthe present invention.

The lead fingers 401, the integrated circuit die 403, and the ball bonds405 are embedded in an encapsulant 406. The lead fingers 401 and theball bonds 405 are generally made of conductive materials, and theencapsulant 406 is of an insulating material.

A medium device configuration 410 is shown with a medium passive device412 extending between lead fingers 414 and 416 having straight tips andlead finger grooves 415 and 417, respectively.

A small device configuration 420 has a small passive device 422extending between a lead finger 424, having a tip extension on one side,and a lead finger 426 with a straight tip.

A corner configuration 430 includes a passive device 432 between anextended, long lead finger 434 and an extended, long lead finger 436having a widened tip as required to accommodate the passive device 432.Where the lead fingers generally are parallel one to another, theextended, long lead finger 434 and the extended, long lead finger 436extend perpendicular one to another. The extended, long lead finger 434has a wide groove 435 on one side and the extended, long lead finger 436has an offset tip with a groove 437.

A large device configuration 440 has a large passive device 442 betweentwo lead fingers 444 and 446, both of which have their tips oppositelyoffset so as to accommodate the large passive device 442 between leadfinger grooves 445 and 447.

Referring now to FIG. 4B, therein is shown the structure of FIG. 4Aalong line 4B-4B. The integrated circuit package 400 has the lead finger416 with a blind groove 450 containing the medium passive device 412 andsolder 452. The ball bonds 405 support the integrated circuit die 403,often referred to as a flip chip, in the encapsulant 406. The flip chiphas contacts on top and is flipped to the position shown.

The integrated circuit package 400 also includes a solder mask 454having openings therein for further ball bonds 456 to extendtherethrough. The integrated circuit package 400 is often referred to asa ball grid array (BGA).

Referring now to FIG. 5A, therein is shown a plan view of an integratedcircuit package 500 according to a still further embodiment of thepresent invention with an integrated circuit die and ball bonds shown bydotted lines. The integrated circuit package 500 has a number of leadfingers 501 around the perimeter thereof to which an integrated circuitdie 503 is attached by ball bonds 505. The lead fingers 501 arerepresentative of different types of lead fingers, which may be used inaccordance with the present invention.

The lead fingers 501, a leadframe paddle 502, an integrated circuit die503, and the ball bonds 505 are embedded in an encapsulant 506. The leadfingers 501, the leadframe paddle 502, and the ball bonds 505 aregenerally made of conductive materials, and the encapsulant 506 is of aninsulating material.

In FIG. 5A, grooves are formed in the lead fingers 501 and/or theleadframe paddle 502.

A medium device configuration 510 is shown with a medium passive device512 extending between a lead finger 514, having an increased tip width,and the leadframe paddle 502 having a lead finger groove 513 and apaddle groove 515, respectively.

A large device configuration 520 has a large passive device 522 betweena lead finger 524 having an increased tip width and the leadframe paddle502 having a notch 526 to accommodate the large passive device 522. Thelead finger 524 has a lead finger groove 525 and the leadframe paddle502 has a paddle groove 527 at one side of the notch 526.

A large device configuration 530 has a large passive device 532 betweenoppositely enlarged lead fingers 534 and 536 having increased tip widthsand notches to accommodate the large passive device 532. The oppositelyenlarged lead fingers 534 and 536 have lead finger grooves 535 and 537,respectively.

Referring now to FIG. 5B, therein is shown the structure of FIG. 5Aalong line 5B-5B. The integrated circuit package 500 has the lead fingergroove 513 and the paddle groove 515 extending through the lead finger514 and the leadframe paddle 502, respectively, to a solder mask 540.This permits the medium passive device 512 to be thicker for the sameplan view configuration.

The integrated circuit package 500 also includes the solder mask 540 forfurther ball bonds 545, which extend downward therefrom.

The integrated circuit package 500 further is able to make use of theleadframe paddle 502 as a ground plane and/or a heat-spreading plane.

Referring now to FIG. 6A, therein is shown a plan view of an integratedcircuit package 600 according to another embodiment of the presentinvention with an integrated circuit die and ball bonds shown by dottedlines. The integrated circuit package 600 has a number of lead fingers601 around the perimeter thereof to which an integrated circuit die 603is attached by ball bonds 605. The lead fingers 601 are representativeof different types of lead fingers, which may be used in accordance withthe present invention.

The integrated circuit package 600 further includes a leadframe paddle602, which can be of various configurations, upon which the integratedcircuit die 603 is also attached. The lead fingers 601, the leadframepaddle 602, the integrated circuit die 603, and the ball bonds 605 areembedded in an encapsulant 606. The lead fingers 601, the leadframepaddle 602, and the ball bonds 605 are generally made of conductivematerials, and the encapsulant 606 is of an insulating material.

In FIG. 6A, a medium device configuration 610 is shown with a mediumpassive device 612 extending between a lead finger 614 and the leadframepaddle 602. The lead finger 614 has a lead finger groove 613 and theleadframe paddle 602 has a paddle groove 615.

The leadframe paddle 602 also has a groove or a relief 619. The relief619 can be of any configuration but is shown as a broad cross.

Referring now to FIG. 6B, therein is shown the structure of FIG. 6Ataken along line 6B-6B, which better shows the relief 619. The relief619 provides better moldability for the encapsulant 606. The ungroovedor unrelieved portions of the leadframe paddle 602 are sufficientlythick to permit the usual blind and through-grooves for attachment ofpassive devices. The leadframe paddle 602 can continue to act as aground plane and/or heat-spreading plane. The medium passive device 612is held in the lead finger groove 613 and the paddle groove 615 byconductive adhesive 620 and 621, respectively.

Referring now to FIG. 7A, therein is shown a method for manufacturing awire-bonded integrated circuit package in accordance with an embodimentof the present invention. A leadframe 700 has lead fingers 701 and aleadframe paddle 702. The lead fingers 701 have blind grooves 704 and706 provided therein. The leadframe 700 is on an adhesive tape 710 andis covered by a stencil 712 having openings matching the blind grooves704 and 706. A doctor blade 714 is shown drawing solder paste 716 acrossthe surface of the stencil 712 in the direction indicated by the arrow718. Solder paste 720 fills the blind groove 704.

Referring now to 7B, therein is shown the structure of FIG. 7A afterremoval of the stencil 712 and positioning of the passive devices 722and 724 and reflow soldering to convert the solder paste 716 into solderto hold the passive devices 722 and 724 in place.

Referring now to FIG. 7C, therein is shown the structure of FIG. 7Bafter deposition of a heat conductive bonding compound 726, such as anepoxy, from a nozzle 728.

Referring now to FIG. 7D, therein is shown the structure of FIG. 7Cafter positioning of a wire-bonded integrated circuit die 730.

Referring now to FIG. 7E, therein is shown the structure of FIG. 7Dafter bonding wires 732 between the wire-bonded integrated circuit die730 to the lead fingers 701.

Referring now to FIG. 7F, therein is shown the structure of FIG. 7Eafter deposition of an encapsulant 734. Depending upon the encapsulant734, the encapsulant material can be molded and cured.

Referring now to FIG. 7G, therein is shown the structure of FIG. 7Fafter de-tape, or removal of the adhesive tape 710.

Referring now to FIG. 7H, therein is shown the structure of FIG. 7Gafter singulation. Singulation is the process by which each individualintegrated circuit package is cut from a strip into an individualintegrated circuit package 735 for a leadless package.

Referring now to FIG. 7I, therein is shown the structure of FIG. 7F inan alternate embodiment showing the formation of a BGA package. In FIG.7I, openings or apertures 740 in the adhesive tape 710, or a soldermask, are formed by chemical etching, photolithographic processing, orlaser cutting.

Referring now to FIG. 7J, therein is shown the structure of FIG. 7Iafter attaching solder balls 742 and reflowing to form a BGA package.

Referring now to FIG. 7K, therein is shown the structure of FIG. 7Jafter singulation to form an individual integrated circuit package 745for a wire-bonded BGA package.

Referring now to FIG. 8A, therein is shown a method for manufacturing aBGA integrated circuit package in accordance with another alternateembodiment of the present invention. A leadframe 800 has lead fingers801 that have blind grooves 804 and 806 provided therein. The leadframe800 is on an adhesive tape 810 and is covered by a stencil 812. Thestencil 812 has apertures or openings 805 and 807 through to the leadfingers 801. A doctor blade 814 is shown drawing solder paste 816 acrossthe surface of the stencil 812 in the direction indicated by the arrow818. The solder paste 816 fills the blind groove 804 to form solderpaste 820 and the opening 805 to form solder paste 821.

Referring now to FIG. 8B, therein is shown the structure of FIG. 8Aafter the removal of the stencil 812 to leave the solder paste 821 and823. Passive devices 822 and 824 are then positioned in the respectiveblind grooves 804 and 806.

Referring now to FIG. 8C, therein is shown the structure of FIG. 8Bafter a ball-bonded integrated circuit die 830 is attached by reflowingthe solder paste 821 and 823 into ball bonds 832 and 834. The reflowattaches the passive devices 822 and 824 to the lead fingers 801.

Referring now to FIG. 8D, therein is shown the structure of FIG. 8Cafter encapsulation in an encapsulant 836.

Referring now to FIG. 8E, therein is shown the structure of FIG. 8Dafter the formation of apertures 840 in the adhesive tape 810.

Referring now to FIG. 8F, therein is shown the structure of FIG. 8Einverted for ball attach and reflow of solder balls 842 in the apertures840 of FIG. 8E.

Referring now to FIG. 8G, therein is shown the structure of FIG. 8Finverted and singulated by a blade 844 to form a BGA package 850.

Referring now to FIG. 8H, therein is shown the structure of FIG. 8E inan alternate method of manufacture in accordance with the presentinvention. The structure of FIG. 8E is inverted. A stencil 860 ispositioned over the adhesive tape 810 with holes 862 lined up with theapertures 840. A doctor blade 864 is shown drawing solder paste 866across the surface of the stencil 860 in the direction indicated by thearrow 868. Solder paste 870 fills the apertures 840 and the holes 862.

Referring now to FIG. 8I, therein is shown the structure of FIG. 8Hafter removal of the stencil 860 of FIG. 8H and reflow of the solderpaste 870 to form solder bumps 872. The structure has been inverted andsingulated by the blade 844 to form a solder attach integrated circuitpackage 875.

Referring now to FIG. 9A, therein is shown a method for manufacturing aBGA integrated circuit package in accordance with another alternateembodiment of the present invention. The leadframe 900 has lead fingers901 that have blind grooves 904 and 906 provided therein. The leadframe900 is on an adhesive tape 910 and is covered by a stencil 912. Thestencil 912 has apertures or openings 905 and 907 through to the leadfingers 901. A doctor blade 914 is shown drawing solder paste 916 acrossthe surface of the stencil 912 in the direction indicated by the arrow918. The solder paste 916 fills the blind groove 904 to form solderpaste 920 and the opening 905 to form solder paste 921.

Referring now to FIG. 9B, therein is shown the structure of FIG. 9Aafter the removal of the stencil 912 to leave the solder paste 921 and923. Passive devices 922 and 924 are then positioned in the respectiveblind grooves 904 and 906.

Referring now to FIG. 9C, therein is shown the structure of FIG. 9Bafter a ball-bonded integrated circuit die 930 is attached by reflowingthe solder paste 921 and 923 into ball bonds 932 and 934. The reflowattaches the passive devices 922 and 924 to the lead fingers 901.

Referring now to FIG. 9D, therein is shown the structure of FIG. 9Cafter encapsulation in an encapsulant 936.

Referring now to FIG. 9E, therein is shown the structure of FIG. 9Dafter de-tape, or removal of the adhesive tape 910. Thereafter, aleadless ball-bonded integrated circuit package can be formed in asingulation process.

Referring now to FIG. 9F, therein is shown the structure of FIG. 9Eafter the attachment of a dielectric layer 980, such as solder mask, tothe leadframe 900. Openings or apertures 940 are formed in thedielectric layer 980 by chemical etching, photolithographic processing,or laser cutting.

Referring now to FIG. 9G, therein is shown the structure of FIG. 9F inan alternate embodiment showing the formation of a BGA package. Thestructure of FIG. 9G is inverted for ball attach and reflow of thesolder balls 942 in the apertures 940 of FIG. 9F.

Referring now to FIG. 9H, therein is shown the structure of FIG. 9Finverted and singulated by a blade 944 to form a BGA package 950.

Referring now to FIG. 9I, therein is shown the structure of FIG. 9F inan alternate method of manufacture in accordance with the presentinvention. The structure of FIG. 9F is inverted. A stencil 960 ispositioned over the dielectric layer 980 with holes 962 lined up withthe apertures 940. A doctor blade 964 is shown drawing solder paste 966across the surface of the stencil 960 in the direction indicated by thearrow 968. Solder paste 970 fills the apertures 940 and the holes 962.

Referring now to FIG. 9J, therein is shown the structure of FIG. 9I 8Hafter removal of the stencil 960 of FIG. 8H and reflow of the solderpaste 970 to form solder bumps 972. The structure has been inverted andsingulated by the blade 944 to form a solder attach integrated circuitpackage 975.

Referring now to FIG. 10A, therein is shown a method for manufacturing aball-bonded integrated circuit package in accordance with anotheralternative embodiment of the present invention. The leadframe 1000 haslead fingers 1001 and a leadframe paddle 1002. The lead fingers 1001have blind grooves 1004 and 1006 provided therein. The leadframe 1000 ison an adhesive tape 1010 and is covered by a stencil 1012. A doctorblade 1014 is shown drawing solder paste 1016 across the surface of thestencil 1012 in the direction indicated by the arrow 1018. Solder paste1020 fills the blind groove 1004.

Referring now to FIG. 10B, therein is shown the structure of FIG. 10Aafter the removal of the stencil 1012 to leave the solder paste 1021.The passive devices 1022 and 1024 are then positioned in the respectivegrooves 1004 and 1006.

Referring now to FIG. 10C, therein is shown the structure of FIG. 10Bafter a ball-bonded integrated circuit die 1030 is attached and the ballbonds 1032 are formed and the passive devices 1022 and 1024 are reflowedinto position.

Referring now to FIG. 10D, therein is shown the structure of FIG. 10Cafter encapsulation in an encapsulant 1034. The encapsulant 1034 ismolded around each ball-bonded integrated circuit die 1030.

Referring now to FIG. 10E, therein is shown the structure of FIG. 10Dafter de-tape, or removal of the adhesive tape 1010.

Referring now to FIG. 10F, therein is shown the structure of FIG. 10Dafter the attachment of a dielectric layer 1080, such as solder mask, tothe leadframe 900. Openings or apertures 1040 in the dielectric layer1080 are formed by chemical etching, photolithographic processing, orlaser cutting.

Referring now to FIG. 10G, therein is shown the structure of FIG. 10F inan alternate method of manufacture in accordance with the presentinvention. The structure of FIG. 10F is inverted. A stencil 1060 ispositioned over the adhesive tape 1010 with holes 1062 lined up with theapertures 1040. A doctor blade 1064 is shown drawing solder paste 1066across the surface of the stencil 1060 in the direction indicated by thearrow 1068. Solder paste 1070 fills the apertures 1040 and the holes1062.

Referring now to FIG. 10H, therein is shown the structure of FIG. 10Gafter attachment of passive devices 1070 and 1072 and reflow soldering.

Referring now to FIG. 10I, therein is shown the structure of FIG. 10Hafter trim and dam-bar cut of the lead fingers 1001 to a wrap aroundlength. The dambar cut is performed to cut off any joints, which mayprovide pre-encapsulation support for the lead fingers.

Referring now to FIG. 10J, therein is shown the structure of FIG. 10Iafter the forming of the lead fingers 1001 into wrap-around externalleads to provide an external lead integrated circuit package 1075.

Referring now to FIG. 11A, therein is shown a close-up view of leadfingers 1100 and 1102 shown on an adhesive tape 1104. The lead finger1100 has a lead finger groove 1105 with solder paste reservoirs 1106 and1108 at the two corners filled with solder paste before reflowing. Thelead finger 1102 has a lead finger groove 1107 with solder pastereservoirs 1110 and 1112 at the two corners filled with solder pastebefore reflowing. The lead finger grooves 1105 and 1106 are shown asthrough grooves but can also be blind grooves, as indicated by thephantom lines 1114 and 1116, respectively.

Referring now to FIG. 11B, therein is shown the structure of FIG. 11Ahaving a passive device 1120 in the solder formed after reflow solderingof the solder paste which has been printed or dispensed.

Referring now to FIG. 12A, therein is shown one embodiment of thecross-section of FIG. 11B taken along line 12A-12A. The passive device1120 is in the lead finger groove 1105 having a bottom 1205 and thesolder paste is in the reservoirs 1106 and 1108 having respectivebottoms 1206 and 1208. The cross-section shows a vertical thickness ofthe lead finger 1102. The lead finger groove 1105 is shown as beingformed at least halfway through the vertical thickness of the leadfinger 1102 with the connected reservoirs 106 and 108 being formed inthe lead finger 1102 at least halfway through the vertical thickness ofthe lead finger 1102. After solder reflow, the solder paste is convertedinto solder in the groove 1105 and the reservoirs 1106 and 1108 thathold the passive device 1120 in the lead finger 1102.

Referring now to FIG. 12B, therein is shown another embodiment of thecross-section of FIG. 11B taken along line 12B-12B. The passive device1120 is in the lead finger groove 1105 without a bottom and the solderpaste is in the reservoirs 1106 and 1108 having respective bottoms 1206and 1208. The cross-section shows a vertical thickness of the leadfinger 1102. The lead finger groove 1105 is shown as being formed allthe way through the vertical thickness of the lead finger 1102 with theconnected reservoirs 1106 and 1108 being formed in the lead finger 1102at least halfway through the vertical thickness of the lead finger 102.After solder reflow, the solder paste is converted into solder in thegroove 1105 and the reservoirs 1106 and 1108 that hold the passivedevice 1120 in the lead finger 1102.

Referring now to FIG. 12C, therein is shown another embodiment of thecross-section of FIG. 11B taken along line 12C-12C. The passive device1120 is in the lead finger groove 1105 without a bottom and the solderpaste is in the reservoirs 1106 and 1108 without bottoms. Thecross-section shows a vertical thickness of the lead finger 1102. Thelead finger groove 1105 is shown as being formed all the way through thevertical thickness of the lead finger 1102 with the connected reservoirs1106 and 108 being formed in the lead finger 1102 all the way throughthe vertical thickness of the lead finger 1102. After solder reflow, thesolder paste is convened into solder in the groove 1105 and thereservoirs 1106 and 1108 that hold the passive device 1120 in the leadfinger 1102.

Referring now to FIG. 13, therein is shown a close-up plan view of thepassive device 1120 showing solder 1300 filling the gaps between thepassive device 1120 and the lead fingers 1100 and 1102. The solder 1300fills the gap by capillary effect during solder reflow.

Referring now to FIG. 14, therein is shown a method 1400 for forming anintegrated circuit package in accordance with the present invention. Themethod 1400 comprises: a block 1402 of providing a leadframe having leadfingers; a block 1404 of forming a groove in a lead finger; in a block1406 of placing a conductive bonding agent in the groove; and a block1408 of placing an electronic device in the groove to be held by theconductive bonding agent.

While the invention has been described in conjunction with a specificbest mode, it is to be understood that many alternatives, modifications,and variations will be apparent to those skilled in the art in light ofthe aforegoing description. Accordingly, it is intended to embrace allsuch alternatives, modifications, and variations which fall within thespirit and scope of the included claims. All matters set forth herein orshown in the accompanying drawings are to be interpreted in anillustrative and non-limiting sense.

1. An integrated circuit package, comprising: a lead finger having ahorizontal length, a horizontal width, and a vertical thickness, thelead finger having a groove formed therein at least halfway through thevertical thickness with a connected reservoir formed therein at leasthalfway through the vertical thickness; a conductive bonding agent inthe groove and the connected reservoir; and an electronic device in thegroove to be held to the lead finger by the conductive bonding agent inthe groove and in the connected reservoir.
 2. The integrated circuitpackage as claimed in claim 1 wherein the lead finger has a tip of atleast one of the configurations of straight, increased width, sideextension, flared, offset, extended, or a combination thereof.
 3. Theintegrated circuit package as claimed in claim 1 further comprising thelead finger formed into an external lead around at least a portion ofthe integrated circuit package.
 4. The integrated circuit package asclaimed in claim 1 wherein: the connected reservoir is adjacent to acorner of the groove; and the groove has a second connected reservoiradjacent to a further corner of the groove for containing the conductivebonding agent.
 5. The integrated circuit package as claimed in claim 1further comprising: a leadframe paddle having the groove providedtherein; a conductive bonding agent in the groove; and the electronicdevice in the groove to be held by the conductive bonding agent.
 6. Theintegrated circuit package as claimed in claim 1 further comprising: anintegrated circuit die bonded by at least one of wire or ball to thelead finger; and at least one of a solder bump or a ball grid array ballformed on the lead finger.
 7. An integrated circuit package, comprising:lead fingers having horizontal lengths, horizontal widths, and verticalthicknesses, the lead fingers extending parallel, perpendicular, and acombination thereof one to another, a pair of lead fingers having blindor through grooves formed therein at least halfway through the verticalthicknesses with connected reservoirs formed therein at least halfwaythrough the vertical thicknesses; a conductive bonding agent in theblind or through grooves; and a passive device in the blind or throughgrooves to be held to the lead finger by the conductive bonding agent inthe grooves and in the connected reservoirs, the passive deviceextending between the pair of lead fingers.
 8. The integrated circuitpackage as claimed in claim 7 wherein: the lead fingers have tips of atleast one of the configurations of straight, increased, side extension,flared, offset, extended, or a combination thereof; the passive deviceincludes a small, medium, or large passive device connected between twoof the lead fingers; and the blind or through grooves are formedproximate the tips of the lead fingers.
 9. The integrated circuitpackage as claimed in claim 7 further comprising: the lead fingersformed into external leads around at least a portion of the integratedcircuit package; and an additional passive device on one of the externalleads exterior to the integrated circuit package.
 10. The integratedcircuit package as claimed in claim 7 wherein: the connected reservoirsare adjacent to a corner of the grooves; and the grooves have a secondconnected reservoir adjacent to a further corner of the grooves forcontaining the conductive bonding agent.
 11. The integrated circuitpackage as claimed in claim 7 further comprising: a leadframe paddlehaving at least a groove, a notch, or a relief provided therein; aconductive bonding agent in at least the groove, the notch, the relief,or a combination thereof; and at least the passive device in the groove,the notch, the relief, or a combination thereof is held by theconductive bonding agent between at least one of the lead fingers andthe leadframe paddle, the integrated circuit die and the groove, thenotch, the relief, or a combination thereof.
 12. The integrated circuitpackage as claimed in claim 7 further comprising: an integrated circuitdie bonded by at least one of a wire or ball to the lead finger; anencapsulant encapsulating the integrated circuit die and the leadfinger; and at least one of a solder bump or a ball grid array ballformed on the lead finger outside the integrated circuit package.